The present invention relates to a computer program called a front-end processor which is executed on a platform provided in an OS (Operating System) for converting code strings entered through an input device into another code strings, such as those for expressing Japanese characters, to be supplied to an application program by way of the OS, and more particularly to that easy to be supplemented with additional functions, for example, to retrieve external resources such as a wording example database or a technical dictionary provided on a CD-ROM (Compact Disk Read Only Memory).
The front-end processor is used for enabling an easy input of characters other than the alphabet and a standard architecture, namely a platform, for the front-end processor is prepared in many operating systems. For example, the IME (Input Method Editor) provided with and operating on the Windows (registered trade mark of Microsoft Corporation in USA) system is a platform for the front-end processor, and various front-end processors conforming to the platform are developed by software providers.
Many of the front-end processors are specialized for a unique function, Japanese character conversion, for instance, but there are some front-end processors provided with additional functions to retrieve external resources for enabling users to obtain supplementary information incident to their basic function. An example of them is disclosed in a Japanese patent application laid open as a Provisional Publication No. 175860/'87 entitled "Japanese Character Converter", wherein is added a function for retrieving a wording dictionary in order to prevent users' mis-wording with homophones. In another Japanese patent application laid open as a Provisional Publication No. 37613/'89 entitled "A Help Method for Electronic Apparatus", a front-end processor provided with an on-line-help function is disclosed.
These conventional front-end processors having additional functions for retrieving external resources can be grouped into two types, those which make use of their own build-in functions for the external resource retrieval, and those where users must beforehand install functions to be used among several retrieving functions prepared by the provider.
In these conventional front-end processors, however, there are left some inconveniences that available additional functions are predetermined without consideration of optional extension, in the former type, and so, it is difficult to assign different start icons for different functions or to set different data communication levels for different functions, even though different external resources may be applied in turn, or that a fairly complicated environment setting is forced to users, in the latter type, such as retrieval start key assignment for each of the external resources to be applied in case they are to be retrieved by way of key-inputs, for example.